Space Vocab. Flashcards
(34 cards)
Solar System
The sun and its family of orbiting planets, moons, and other objects
Galaxy
Millions or billions of stars held together in a group by their own gravity
Universe
Space and all the matter and energy in it
Satellite
An object that orbits a more massive object
Impact Crator
A round pit left behind on the surface of a planet or other body in space after a smaller object strikes the surface
Axis of Rotation
An imaginary line about which a turning body, such as Earth rotates
Revolution
The motion of one body around another, such as Earth in its orbit around the Sun; the time it takes an object to go around once
Season
One part of a pattern of temperature changes and other weather trends over the course of a year.
Equinox
In an orbit, a position and time in which sunlight shines equally on the Northern Hemisphere and the Southern Hemisphere; a time of year when daylight and darkness are nearly equal for most of Earth
Solstice
In an orbit, a position and time during which one hemisphere gets maximum area of sunlight, while the other hemisphere gets its minimum amount; the time of year when days are either longest or shortest, and the angle of sunlight reaches its maximum or minimum
Mare
A large, dark plain of solidified lava on the Moon. The poor all form of mare is maría
Eclipse
An event during which one object in space casts a shadow onto another. On Earth, a lunar eclipse occurs when the Moon moves through Earth’s shadow, and a solar eclipse occurs when the Moon’s shadow crosses Earth
Umbra
The dark, central region of a shadow, such as the cone of complete shadow cast by an object
Penumbra
A region of lighter shadow that may surround an umbra; for example, the spreading cone of lighter shadow cast by a space object
Astronomical Unit
Earth’s average distance from the Sun, which is approximately 150 million kilometers (93 million mi)
Ellipse
An oval or flattened circle
Terrestrial Planet
Earth or a planet similar to Earth that has a rocky surface. The four planets in the inner solar system-Mercury, Venus, Earth, and Mars-are terrestrial planets
Gas Giant
A large planet the consists mostly of gases in a dense form. The four large planets in the outer solar system- Jupiter, Saturn, Uranus, and Neptune-are gas giants.
Asteroid
A small, solid, rocky body that orbits the Sun. Most asteroids orbit in a region between Mars and Jupiter called the asteroid belt.
Comet
A body that produces a coma of gas and dust; a small, icy body that orbits the Sun
Meteor
A brief streak of light produced by a small particle entering Earth’s atmosphere at a high speed
Meteorite
A small object from outer space that passes through Earth’s atmosphere and reaches the surface
Geocentric
Earth is the center of the solar system
Heliocentric
Sun is in the center of the solar system
